Mason 2 has been rearchitected and reimplemented from the ground up, to take advantage of modern Perl techniques (Moose, Plack/PSGI) and to correct long-standing feature and syntax inadequacies. Its new foundations should allow its performance and flexibility to far exceed Mason 1.

So, I figured "why not let Plack take care of it?". I wrote Plack::Middleware::NoMultipleSlashes (a single line of code, really), that cleans those multiple slashes for you, wherever they are in the path.